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What is Cybersecurity?Before we can understand what cybersecurity is and what types of risks and vulnerabilities it contains, we must first comprehend the cyberspace. The term "cyberspace" refers to a collection of communication networks, databases, embedded processors, the internet, and controllers used to exchange electronic documents. Telephone wires, coaxial cables, electromagnetic waves, and fiber-optic connections create a global network environment.Though cyberspace and the Internet are sometimes used interchangeably, the Internet is actually a part of cyberspace. To put it another way, cyberspace is a networked Internet environment.Cyber-security can be defined as the process of defending cyberspace from assault, abuse, harm, ... Read More
What is Subnetting?Subnetting is a process of separating a single physical network into several logical subnetworks (subnets).A network segment and a host segment make up an IP address subnets formed by extracting bits from an IP address's host component and establishing several smaller sub-networks within a more extensive network.Subnetting enables a business to expand its network without securing a new network number from its Internet Service Provider (ISP). Subnetting reduces network traffic while also hiding network complexity.Subnetting is required when a single network number must be distributed across multiple parts of a local area network.Subnets were created to alleviate the ... Read More
Classical CryptographyClassical cryptography employs a number of mathematical approaches to prevent eavesdroppers from learning the contents of encrypted transmissions. The most widely used and widely embraced among them are given below. Throughout the article, the transmitter is referred to as 'Alice, ' the receiver is referred to as 'Bob, ' and an eavesdropper is referred to as 'Eve.'Quantum CryptographyIt is a kind of cryptography that uses "quantum mechanics". The creation of a quantum channel necessitates the use of polarising filters at both the transmitter and receiver ends. As a result, at the transmitter end, we can send pictures with a ... Read More
To increase the distance between boxplots created by using ggplot2, we can reduce the widths of the boxplots and hence the distance between the plots will be automatically increased. This will be required when we have large number of categories for which the boxplots are created.Check out the below given example to understand how it can be done.ExampleFollowing snippet creates a sample data frame −Group
The matrices stored in an array cannot directly have zero at lower triangular or upper triangular positions because assignment in arrays is not straight forward. Therefore, to set lower triangular matrices to zero stored in an R array, we can use for loop.Check out the below given example to understand how it can be done.ExampleFollowing snippet creates a sample array −Array
To combine list elements of different sizes in R, we can use expand.grid function. For Example, if we have a list called LIST that contains elements of different sizes then we can combine those items by using the command given below −expand.grid(LIST)Example 1To combine list elements of different sizes in R, use the following snippet −List1
To display X-axis labels with dash in base R plot, we can use axis function and define the labels manually. For this purpose, we can first create the plot without X-axis labels by using the argument xaxt="n" and then use the axis function.Check out the below example to understand how it can be done.ExampleIn order to display X-axis labels with dash in base R plot, use the following code −plot(5, 5)OutputIf you execute all the above given codes as a single program, it generates the following output −In order to display X-axis labels with dash in base R plot, add ... Read More
To find the groupwise cumulative mean, we can use cummean function of dplyr package.For example, if we have a data frame called df that contains a categorical column say Group and a numerical column say Response then the groupwise cumulative mean can be found by using the command given below −df%>%group_by(Group)%>%mutate(CM=cummean(Response))Example 1Following snippet creates a sample data frame −Group
To combine data frames stored in a list in R, we can use full_join function of dplyr package inside Reduce function.For Example, if we have a list called LIST that contains some data frames then we can combine those data frames by using the below command −Reduce(full_join,LIST)Check out the Example given below to understand the Output of this command.ExampleFollowing snippet creates a sample data frame −df1
To create barplot for some top values in an R data frame, we can subset the required top values inside the barplot function.For example, if we have a data frame called df that contains a categorical column say C and a numerical column for frequency defined as F then the barplot for top five values can be created by using the below mentioned command −barplot(df$F[1:5],names.arg=df$C[1:5])ExampleFollowing snippet creates a sample data frame −Category